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AbstractWe prove an identity involving prime numbers, which gives new elementary proofs of two well-known prime properties. Furthermore, the identity and its corollaries may contribute to a better understanding of the distribution of the primes.

To analyze the frequency, clinical characteristics, and predictors of symptomatic intracerebral hemorrhage (ICH) after intraarterial (IA) thrombolysis with recombinant pro-urokinase (r-proUK) in acute ischemic stroke.

This paper presents the results of an investigalion into the possibility that gangliosido (brain cortex glycosphingolipids) are capable of being functionally incorporated into cell membranes and of interfering with enzymatic activity of the ATPase system on the stria mcularis and spiral ligament in the guinea pig. Labelled gangliosides (3H-GM1) were incorporated into the cell memhranes of the tissues under examination. (Na. K-)ATPase activity increased 10 minutes after intiravenous injection of gangliosides and prevented the decrease in (Na-, K-)ATPase system produced by etha-crynic acid. The action of gangliosides on the (Na. K-)ATPase system is discussed.

The Remote Control Centers (RCC) represent the third hierarchical level of the ENEL (Italian Electricity Board) Power Generation and Transmission Control System. The power system control is performed by the National Control Center (NCC) and the eight Area Control Centers (ACC). The RCCs are responsible for carrying out the switching operations and the monitoring of unmanned generation and transmission stations. The RCCs of the new generation will replace the existing RCCs which control the majority of the stations (about 80%).

The in vitro activity of the new aminoglycoside dactimicin in comparison to amikacin was tested alone and in combination with piperacillin, mezlocillin and ceftazidime against freshly isolated clinical pathogens. Dactimicin was more active than amikacin againstEnterobacter cloacae, Providencia rettgeri and Salmonella spp., and less active than amikacin againstEscherichia coli, Pseudomonas aeruginosa andAcinetobacter anitratus. Using the checkerboard technique, the combination of either dactimicin or amikacin with the other drugs was shown to result in synergistic interaction against most of the 23 strains tested. Dactimicin-ceftazidime and amikacin-ceftazidime were the most effective combinations, demonstrating synergism against 91 % and 95 % of the isolates respectively. Antagonism was not encountered. Using the time-kill method, synergism was seen in most cases, indifference rarely being seen; antagonism was not observed. Dactimicin induced a post-antibiotic effect which ranged from 1 h forEnterobacter cloacae to 2.4 h forEscherichia coli. An average post-antibiotic effect of 0.6 h was also seen when dactimicin was combined with piperacillin, mezlocillin and ceftazidime. The findings indicate that dactimicin compares favorably in vitro with amikacin and suggest that clinical trials with this drug alone or in combination are warranted.

Mice were orally vaccinated with liposomes coated with filamentous hemagglutinin (FHA) and detoxified pertussis toxin (PT) of Bordetella pertussis. FHA- and PT-specific immunoglobulin G (IgG) was detected in serum, and both IgG and IgA were detected in lung washes following the immunization. Antibody responses in mice immunized with liposomes coated with FHA and PT were significantly higher than those in mice immunized with free FHA and PT, which demonstrated the adjuvanticity of the liposome carrier. The results indicate the potential usefulness of this approach for eliciting immune responses against FHA and PT (and perhaps other pertussis antigens) in humans and its possible utility in large-scale vaccination to protect against both B. pertussis infection and disease.

Authors examine the case report of pertrochanteric femoral fractures treated with the D.H.S. screw plate at 135° in three years (from june 1987 to august 1990) at the Istituto Ortopedico Galeazzi of Milan.During this period of time 92 patients have been operated, and 38 have been clinically controlled with mid follow-up of 54 months.Authors describe characteristics of this synthesis means comparing it with others (Thorton nail-plate, Ender nails, etc.) commonly used.Finally, they compare the obtained results with those mentioned in literature.

A new method of dental fluorine prophylaxis based on the chemical reaction induced by UV irradiation in dental enamel has been presented. Fluorine ions from a gel topic can be retained to the dental apatite in the lamp-irradiated samples at about 70% and in the laser-irradiated samples at about 80% of the maximum deposited value. The19F(p,α)16O nuclear reaction was used to measure the fluorine concentrations in the first 3 μm of the enamel of healthy teeth before and after the gel topic applications with and without UV irradiation. This method of dental prefenction resolves the problem of the traditional fluorine prophylaxis which brings fluorine in the enamel without binding the apatite. Con questo lavoro viene presentato un nuovo metodo di fluoroprofilassi dentale basato su una reazione chimica indotta da irraggiamento UV dello smalto dentario. Gli ioni fluoro di un gel applicato topicamente sullo smalto vengono ritenuti dall'apatite dentaria al 70% ed all'80% del valore di massima deposizione per campioni irradiati con lampada o con luce laser, rispettivamente. La reazione nucleare19F(p,α)16O è stata adoperata per misurare le concentrazioni di fluoro nei primi 3 μm dello smalto dio denti sani prima e dopo l'applicazione del gel con e senza irraggiamento UV. Questo metodo di prevenzione dentale risolve il problema della tradizionale fluoroprofilassi che apporta fluoro allo smalto senza legarlo all'apatite. Предлагается новый метод зубной фторовой профилактики, основанной на химической реакции, индуцированной ультрафиолетовым облучением зубной эмали. Ионы фтора могут удерживатжся из геля в зубном апатите при облучении лампой на 70% и при облучении лазером на 80% от максимальной нанесенной величины. Используется ядерная реакция19F(p,α)16O для измерения концентраций фтора в первых 3 мкм эмали здоровых зубов до и после нанесения гелия с и без ультрафиолетового облучения. Этот метод решает проблему традиционной фторовой профилактики, который позволяет вносить фтор в эмаль без повреждения апатита.

Streptococcus pyogenes organisms (group A streptococci) are considered to be highly adhesive extracellular pathogens. However, it has recently been reported that S. pyogenes has the capacity to efficiently invade eukaryotic cells. In this study, we demonstrate that the interaction of S. pyogenes fibronectin-binding protein (SfbI) with fibronectin on nonphagocytic HEp-2 cells triggers bacterial internalization. Blocking of the SfbI adhesin by either antibodies against the whole protein or antibodies against the fibronectin-binding domains of SfbI, as well as pretreatment of HEp-2 cells with purified SfbI protein, prevents both S. pyogenes attachment and internalization. Inert latex beads precoated with the purified SfbI protein are ingested by eukaryotic cells, demonstrating that SfbI is per se enough to trigger the internalization process. Experiments performed with a recombinant SfbI domain encompassing the two fibronectin-binding regions of the SfbI molecule demonstrated that these binding regions are essential and sufficient to activate uptake by HEp-2 cells. These results demonstrate that the fibronectin-binding protein SfbI is involved in both S. pyogenes' attachment to and ingestion by HEp-2 cells and contribute to elucidation of the underlying molecular events leading to eukaryotic cell invasion by S. pyogenes.

Endoscopically inserted stents are used for the palliation of obstructive jaundice, but infections and blockage of these stents by biliary sludge and bacterial biofilm may develop, presenting major complications. To analyze which bacteria are involved in this process, 25 biliary stents were examined. Eighty-one microorganisms were isolated: 59 gram-negative bacteria (54Enterobacteriaceae and 5Pseudomonas aeruginosa), 19 gram-positive bacteria (allEnterococcus spp.), and 3Candida albicans. TheEnterobacteriaceae were sensitive to netilmicin (100%), imipenem (98%), ciprofloxacin (96%), cefotaxime (69%), and piperacillin (57%), whereasEnterococcus spp. were sensitive to imipenem (79%), piperacillin (75%), ciprofloxacin (63%), and ampicillin (58%). The unpredictable aetiology and high rates of antibiotic resistance suggest that bacteriological monitoring is mandatory to avoid treatment failures in these patients.

In this paper a code for the solution of nonlinear thermo-magnetic problems, arising in the transient analysis of thermal and electromagnetic fields in resistive toroidal field coils of tokamak devices, is presented. A formulation based on the electric vector potential T and the magnetic total scalar potential Ψ for the analysis of the thermo-magnetic skin effect phenomenon in the toroidal field coils of proposed tokamaks has been used, and the results obtained are reported, reviewed and discussed. [ABSTRACT FROM AUTHOR]

In collaboration with O. Sala and G. Molinari, the author has been able to establish, through physiopathological tests, the different thermic and ultrasonic actions developed in the endolymph and in the ampullar cristae by low intensity ultrasonic irradiation applied directly on the osseous labyrinth. Both actions were controlled by physical apparatuses. A special analysis was devoted to the physiological study of the different movements engendered in the endolymph by ultrasonic irradiation. The results obtained furnish the explanation of the characteristics of the nystagmus, appearing during the ultrasonic irradiation, effected in man when ultrasound is applied in severe cases of Ménière's disease.

Experimental investigations in the cat have demonstrated the following modifications of the activity of the vestibular nuclei: (a) galvanic stimulation of the receptors causes either increase or reduction or no change of activity in deitersian units; (b) stimulation of the temporal area causes changes of frequency and rhythm in ipsilateral and sometimes in contralateral deitersian units.

Electroneurographic investigations carried out on afferent fibres of the recurrent nerve associated with laryngeal slowly adapting receptors are described in this paper. The modifications of the afferent discharges of the recurrent nerve due to passive stretch and electrical stimulation applied to the intrinsic laryngeal muscles are highly suggestive of muscle spindle activity. Other proprioceptors showed the functional characteristic of the proprioceptors "in series" with the fibres of a muscle. There is now functional evidence that the intrinsic laryngeal muscles are provided with a stretch-receptor mechanism. This should account for the existence of a myotatic control of these muscles.

The ultrasonic irradiation of the hypophysis, directly performed by Arslan's technique, leads to a clear inhibition of the hypophyseal function.

A large system of wire proportional chambers is being constructed for the readout of the High-Density Projection Chamber of the DELPHI experiment at the Large Electron-Positron (LEP) storage ring. The system consists of 144 chambers, each 0.3-m/sup 2/, and read out via cathode pads. located at the end of the HPC drift volume. The authors discuss the design of the readout chamber; the chamber construction, the mechanical tolerances and gain uniformity, and the performance.<>

Exposure to subinhibitory concentrations (4–8 µg/ml) of azithromycin resulted in loss of motility inProteus mirabilis strains and a significant reduction of motility inPseudomonas aeruginosa strains. Examination revealed that the loss of motility was due to a total absence of flagella inProteus mirabilis while the poor motility observed inPseudomonas aeruginosa was due to absence of flagella in the majority of the population. Since motility may be considered a pathogenicity trait in the two species, these results confirm the unusual ability of azithromycin to reduce the expression of virulence factors in gram-negative pathogens.

The fertility rates in cattle inseminated with semen diluted in standard egg yolk-citrate diluent and in homogenized centrifuged egg yolk (UOC) diluent were compared, the semen being used on a split-sample basis on the second and third days after collection. Significant improvements in the pregnancy rates were obtained on both days of use with UOC diluent; the standard diluent showed a significant drop in the pregnancy rates from the second to third day of use whereas with the UOC diluent there were no significant differences over this storage period.

Abstract This paper presents a study of the mechanical response of hexachiral honeycombs with transversally curved ligaments under planar uniaxial tensile, compressive and shear loads. The impact of the chiral cell design parameters on the resulting macroscopic behaviour is assessed utilising finite elements calculations. It is shown that the presence of ligament curvature permits to attain mechanical responses which are not achievable through conventional chiral honeycomb designs. In addition, the resulting responses exhibit, for all considered load cases, significant tunability through the investigated geometrical design parameters. Two chiral lattices with identical geometries, only differing in their ligament curvature, were manufactured and experimentally tested to validate the finite elements predictions. A connection and assembly strategy is presented and utilised, offering a fast and robust approach to build larger finite lattice structures through 3D printed single basic cells. The hexachiral lattices were tested in tension, compression and in-plane shear, showing good agreement with the numerical predictions. [ABSTRACT FROM AUTHOR]

A multicentre in-vitro study was undertaken to evaluate the susceptibility of bacterial pathogens isolated in different Italian hospitals to meropenem. A total of 1399 aerobic and 452 anaerobic strains was analysed. Comparative agents were imipenem, cefotaxime, ceftazidime, ceftriaxone, piperacillin, ciprofloxacin, genta-micin, amikacin, plus vancomycin when appropriate. The MIC ranges (mg/l) of meropenem were: 0.015–2 for Klebsiella spp., Proteus spp., Morganella morganii and Providencia spp.; < 0.008–1 for Escherichia coli; 0.016–32 for Serratia spp.; 0.03–2 for Enterobacter spp. and Citrobacter spp.; 0.03– > 128 for Acinetobacter anitratus; 0.03–32 for Pseudomonas spp.; < 0.008–0.5 for Haemophilia spp. and Neisseria spp.; 0.015–64 for Staphylococcus spp.; 0.06– > 128 for Enterococcus spp.; < 0.008-0-25 for Streptococcus spp.; 0.016–8 for Fusobacterium spp.; 0.03–8 for Bacteroides spp.; < 0.06–0.5 for anaerobic Gram-positive cocci; 0.08–2 for Clostridium spp. Mero-penem exhibited superior antibacterial activity against the aerobic and anaerobic strains tested when compared to the other β-lactam drugs. The new carbapenem was as active as ciprofloxacin and more active than imipencm and the aminoglycosides against Enterobacteriaceae and Ps. aeruginosa. It was also more active than ciprof-loxacin against most strains of Gram-positive cocci. Meropenem was slightly less potent than imipenem against staphylococci and enterococci, with the exception of oxacillin-susceptible Staph. aureus against which meropenem and imipenem exhibited similar antibacterial activity.